The aerial cableway is used as the carrying means for carrying the woods from the forest. The woods can be easily conveyed by the aerial cableway in the steep slanting regions such as the regions between the mountains, valleys, and the like. The aerial cableway is constituted by suspending the steel cables between the summit of the mountain having the steep slanting surface and the foot of this mountain or in the valley between the mountains. The carrying apparatus which is operated by the radio wave is suspended from the steel cables, thereby suspending and transporting objects to be conveyed.
Most of the conventional carrying apparatuses are of the type of what is called one-shaft one-body in which one drive is provided to move the carrying apparatus while manually operating the sub cableway. However, when the carrying apparatus is obliquely upwardly moved in the steep slanting district, there is a problem such that the drive wheel slips and the carrying apparatus is not smoothly moved because the friction which is caused between the drive wheel and the sub cableway is small. On the other hand, when the carrying apparatus is moved downwardly, there is a fear of runaway of the carrying apparatus since the braking performance is bad, so that it is dangerous. Further, a large total weight of the carrying apparatus and objects to be conveyed acts on one sub cableway, so that there is a risk that the sub cableway is likely to be cut or broken. Therefore, there is a serious problem in that the carrying apparatus recklessly runs if the sub cableway is cut during the movement in the steep slanting region. Thus, the improvement of the conventional carrying apparatus is demanded.
On the other hand, in the thinning or full felling region, or in the region near those regions where the cableway passes, the hoisting cable and lateral hanging cable are repeatedly vertically lifted up and down, so that many standing trees and the like in those regions are damaged. The positions of the workers who control the operations to pull in and out various cables such as lateral hanging cable, towing cable, hoisting cable, and the like are unconditionally determined on the basis of the suspending of the cables and the function of the conventional carrying apparatus. The workers cannot operate the cables from the unobstructed locations. Consequently, it is very inconvenient and dangerous.
When the conventional carrying apparatus as mentioned above is used, the cables are suspended in the following manner. For example, in the case of carrying the cut woods from a square felling region 201 as shown in FIG. 1, an aerial cableway 202 is first suspended so as to cross the square felling region 201. The woods in the regions just below the cableway 202 and in a hatched portion 203 near that region are cut and conveyed to the road side. After completion of the felling of the woods, one pole 204 is moved by a predetermined distance and another aerial cableway 202a is suspended. The woods in the region just below the cableway 202a and in a hatched portion 205 near this region are cut and conveyed. In this manner, it is necessary to sequentially suspend the cableways in order to cut down and carry the woods. Therefore, much labors and costs are required to sequentially newly suspend the cableways. The objects to be conveyed cannot be vertically lifted up and down at a desired single position in the carrying region. For example, in the thinning district or the like in the forest when the woods which were thinned out are carried, the remaining standing trees and the cut woods to be conveyed are damaged by the contact, collision, and the like. On the other hand, in the case of conveying the woods by passing through the area above the non-felling region and the like, the forest at the wood passing location is ruined by the lateral hanging cables and hoisting cables for the hooks serving as the means for hanging up objects to be carried and the like. To prevent this, it is necessary to cut down or thin out the woods in a line form in order to form the passages adapted to suspend the cables. In addition, the workers must always exist at the loading positions when the objects to be carried are loaded and the like. Consequently, the conventional carrying apparatus has many drawbacks such that much labors are required, it is dangerous, many workers are necessary, and the like.
FIG. 2 shows another example of the conventional carrying apparatus. In the case of carrying, for example, the cut woods from such an L-shaped configuration of the ground as shown in FIG. 2, there are also many inconveniences similar to the above. The two-stage wood collecting system which needs two main cableways (or the multi-stage wood collecting system in dependence on the configuration of the ground) must be adopted. Thus, in this case, there are large technical and economical drawbacks.
Moreover, if the conventional one-shaft and one-body carrying apparatus having the swing arms is used, the effect of the swing arms can be presented by a certain degree. However, the driving force and braking force lack because of the single body. The movement range along the cableway suspended in accordance with the steep configuration of the ground is extremely limited and the effect of the swing arms cannot be sufficiently obtained. Consequently, there is a drawback such that the sufficient function of the carrying apparatus cannot be presented as a whole.